Stand with lifting and lowering function

ABSTRACT

A stand includes a frame, a drive, and a moving support member; the frame has two opposing walls, and a base on a bottom thereof, which has two opposing upright parts; the drive includes a driving unit joined to the upright parts of the base, a driven shaft passed through the upright parts and pivoted on the opposing walls, chain wheels on two ends of the driven shaft, and two loop-shaped motion units passed over and engaged with respective ones of the chain wheels; the moving support member is joined to the loop-shaped motion units at two ends thereof by means of a coupling structure so as to be adjusted in height by means of operating the drive; L-shaped sliding pieces are secured on corners of the moving support member and propped against frame wall portions, which are joined to edges of said opposing walls of the frame.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a stand with lifting and lowering function, more particularly one, which has a relatively simple structure and low manufacturing cost, and takes relatively little time to assemble, and which can operate smoothly.

2. Brief Description of the Prior Art

Shown in FIG. 6 is a currently existing stand for holding an article such as a television, which can be a cabinet 71 for holding various objects. And, a television 72 is positioned on top of the cabinet.

Because such a stand doesn't have lifting and lowering function, it isn't suitable for use in a ship cabin, which has a relatively limited space. In other words, such a stand doesn't allow flexible use of the space of a ship cabin.

As shown in FIG. 7, another currently existing television stand includes a frame 81, a drive 82, and a moving supporting member 83; the drive 82 comprises a driving unit 821, a driven shaft 822, and two loop-shaped motion units 83; the driving unit 821 and the driven shaft 822 are disposed side by side between two opposing lateral wall portions of the frame 81 in a horizontal position; the driving unit 821 has a drive gear 8211 for passing on motion of the driving unit 821 to the driven shaft 822 while the driven shaft 822 has driving chain wheels 8221 on two ends thereof; the loop-shaped motion units 823 are arranged on respective ones of inner sides of the opposing lateral wall portions of the frame 81, and passed over and engaged with respective ones of the driving chain wheels 8221; the moving support member 83 is joined to the loop-shaped motion units 823 at two ends thereof. Thus, the moving support member 83 can be moved up and down to change the height of an article held thereon by means of controlling the driving unit 82.

However, the stand would occupy relatively much area of the floor of a ship cabin because the driving unit and the driven shaft are arranged side by side to increase the depth of the stand, i.e. the distance from the front to the back of the stand.

As shown in FIG. 8, a lifting and lowering device was taught in U.S. Pat. No. 6,494,150, which includes a base 91, a driving unit 92, fixed straight rods 93, threaded rods 94, a horizontal driving shaft 95, a transmission mechanism 96, and a moving support member 99 for holding articles. The horizontal driving shaft 95 is connected to the transmission mechanism 96 as well as a transmission gear 921 of the driving unit 92 while the threaded rods 94 are joined to the transmission mechanism 96 such that rotational motion of the driving unit 92 will be passed on to the threaded rods 94. Threaded sleeves 941 is positioned around and threaded engaged with respective ones of the threaded rods 94. And, there are moving sleeves 98 positioned around respective ones of the fixed straight rods 93; the moving sleeves 98 are connected to the threaded sleeves 941 by means of connecting elements 97. The moving support member 99 is securely joined to the moving sleeves 98. Thus, the threaded sleeves 941 will be linearly displaced along the threaded rods 94 when the driving unit 92 is running, thus causing change to the height of the moving sleeves 98 and the moving support member 99.

Such a lifting and lowering device has a disadvantage: it takes relatively much time to adjust the moving support member to a predetermined height because the threaded sleeves moves along the threaded rods very slowly; furthermore, there is possibility of the moving sleeves coming into contact with the fixed straight rods in such a manner as to fail to move smoothly, thus hindering adjustment of the height of the moving support member.

SUMMARY OF THE INVENTION

It is a main object of the present invention to provide an improvement on a stand with lifting and lowering function to overcome the above-mentioned problems.

A stand according to an embodiment of the invention includes a frame, a drive, and a moving support member. The frame has two opposing wall portions, and a base on a bottom thereof, which has two opposing upright parts. The drive includes a driving unit joined to the upright parts of the base, a driven shaft passed through the upright parts and pivoted on the opposing walls, chain wheels on two ends of the driven shaft, and two loop-shaped motion units passed over and engaged with respective ones of the chain wheels; the driving unit has an output shaft, which has a driving gear thereon, and passed through one of the upright parts of the base. The moving support member is joined to the loop-shaped motion units at two ends by means of a coupling structure. The driven shaft has a driven gear thereon, which engages the driving gear. L-shaped sliding pieces are secured on corners of the moving support member and propped against other wall portions of the frame, which are joined to said opposing wall portions; thus, the moving support member can move up and down smoothly along the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood by referring to the accompanying drawings, wherein:

FIG. 1 is an exploded perspective view of the present invention,

FIG. 2 is a perspective view of the present invention,

FIG. 3 is a front sectional view of the present invention,

FIG. 4 is a lateral sectional view of the present invention,

FIG. 5 is a top sectional view of the present invention,

FIG. 6 is a front view of the first prior art,

FIG. 7 is a perspective view of the second prior art, and

FIG. 8 is a front sectional view of the third prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1 to FIG. 5, a preferred embodiment of a stand with lifting and lowering function includes:

(a) a frame 1, the frame 1 comprises:

two opposing hollow holding bodies 11, which are a distance apart; each of the hollow holding bodies 11 has a pair of opposing first wall portions 111, and a lateral wall portion (not numbered) between the opposing first wall portions 111; the lateral wall portions of both the hollow holding bodies 11 face each other;

a base 12 disposed between lower ends of the opposing hollow holding bodies 11, the base 12 has first and second opposing upright parts; the first upright part of the base 12 has through holes 121 and 122 while the second upright part of the base 12 has a through hole 122 opposing the through hole 122 of the first upright part;

(b) a drive 2, the drive 2 comprises:

a driving unit 21 disposed in a lower portion of the frame 1, the driving unit 21 is fitted to both the upright parts of the base 12 of the frame 1 with an output shaft thereof passing through the through hole 121 of the first upright part; the driving unit 21 has a driving gear 211 on the output shaft;

a driven shaft 22 disposed in a lower portion of the frame 1, the driven shaft 22 is passed through the through holes 122 of both the upright parts of the base 12 of the frame 1, and pivoted at two ends thereof on the lateral wall portions of the hollow holding bodies 11 of the frame 1; the driven shaft 22 has a driven gear 221 thereon, which engages the driving gear 211 of the driving unit 21; the driven shaft 22 has two driving chain wheels 222 thereon, which are joined to two ends of the driven shaft 22 respectively;

a pair of loop-shaped motion units 23, the loop-shaped motion units 23 are disposed in the opposing hollow holding bodies 11 of the frame 1 respectively, and are each passed over and engaged with a corresponding said driving chain wheel 222 fitted on the driven shaft 22 so that rotation of the driven shaft 22 can cause motion of the loop-shaped motion units 23 around the driving chain wheels 222; each of the loop-shaped motion units 23 has spaced-apart section holes 231 along the whole length thereof;

(c) a moving support member 3 for holding an article thereon, which is interposed between and coupled at two ends to the loop-shaped motion units 23 so as to move with the loop-shaped motion units 23, the moving support member 3 includes two lateral sides 31 at the two ends thereof, a coupling structure 32, and two front and two rear L-shaped sliding pieces 33, which have an L-shaped cross-section, wherein:

the coupling structure comprises:

two laid-down U shaped pieces 321, which are each secured on a respective said lateral side 31; each of the laid-down U shaped pieces 321 has a containing hollowness 3211, and a pair of opposing through holes 3212 on two opposing sides thereof;

two threaded fixing elements 322, which are each passed through the opposing through holes 3212 of a respective said laid-down U shaped piece 321 as well as one of the section holes 231 of a corresponding said loop-shaped motion unit 23;

two nuts 323, the nuts 323 are each securely joined to a respective said threaded fixing element 322; thus, the moving support member 3 is joined to and movable together with the loop-shaped motion units 23;

the front L-shaped sliding pieces 33 are secured on front ends of both the lateral sides 31 of the moving support member 3 respectively while the rear L-shaped sliding pieces 33 are secured on rear ends of both the lateral sides 31 respectively; furthermore, the space between two sides of each of the front L-shaped sliding pieces 33 faces forwards, and the space between two sides of each of the rear L-shaped sliding pieces 33 faces rearwards; each of the L-shaped sliding pieces 33 is inserted in a corresponding said hollow holding body 11 of the frame 1 from a first one of the two sides thereof, and is propped at said first side against an inner side of a corresponding said first wall portion 111 of the frame 1 such that the moving support member 3 will move up and down smoothly along the hollow holding bodies 11 of the frame 1 when the driving unit 21 of the drive 2 is running.

Therefore, the moving support member 3 can be moved up and down to adjust height by means of operating the drive 2; referring to FIG. 1 to FIG. 5, when the driving unit 21 of the drive 2 is actuated for the output shaft with the driving gear 211 to rotate in a first direction, the rotational motion will be passed on to the loop-shaped motion units 23 through the driven gear 221, the driven shaft 22, and the driving chain wheels 222, and in turn the moving support member 3 will be lifted, which is coupled at the two ends to the loop-shaped motion units 23 by means of the coupling structure 32. And, when the driving unit 21 of the drive 2 is actuated for the output shaft with the driving gear 211 to rotate in a second direction opposite to the first one, the moving support member 3 will be lowered.

In addition, because each of the L-shaped sliding pieces 33 is propped against an inner side of a corresponding said first wall portion 111 of the frame 1 at one of two sides thereof, the moving support member 3 will move up and down smoothly along the hollow holding bodies 11 of the frame 1 after the driving unit 21 of the drive 2 is actuated.

From the above description, it can be seen that the present invention has the following advantages:

1. The moving support member of the stand can be moved up and down to adjusted height because it is coupled to the loop-shaped motion units by means of the coupling structure. Therefore, the stand is suitable for use on a ship, allowing flexible use of the relatively limited space of a cabin in the ship.

2. The stand of the present invention has a relatively simple structure and low manufacturing cost, and takes relatively little time to assemble.

3. The driving unit and the driven shaft are arranged one on top of the other therefore the depth of the stand, i.e. the distance from the front to the back of the stand, is relatively small, and the stand will occupy less area of the floor of a ship cabin.

4. The moving support member has the L-shaped sliding pieces secured on front and rear ends of the two lateral sides thereof, and each L-shaped sliding piece is held in a corresponding said hollow holding body of the frame and propped against the inner side of a corresponding said first wall portion of the frame at one of two sides thereof. Therefore, the moving support member can move up and down smoothly between the hollow holding bodies of the frame. 

1. A stand with lifting and lowering function, comprising (a) a frame including two opposing lateral wall portions, (b) a drive inside the frame, the drive including: a driving unit disposed in a lower portion of the frame, the driving unit having an output shaft with a driving gear; a driven shaft disposed in a lower portion of the frame, the driven shaft being pivoted on the lateral wall portions of the frame at two ends thereof; the driven shaft having a driven gear thereon, which engages the driving gear of the driving unit; the driven shaft having two driving chain wheels thereon; a pair of opposing loop-shaped motion units, the loop-shaped motion units being arranged on inner sides of the lateral wall portions of the frame respectively; the loop-shaped motion units being each passed over and engaged with a corresponding said driving chain wheel on the driven shaft; and (c) a moving support member; the stand being characterized by: the frame including: two opposing hollow holding bodies, each of the hollow holding bodies including a pair of opposing first wall portions, and one said lateral wall portion joined to the opposing first wall portions; and a base secured on a bottom thereof, the base having first and second opposing upright parts; each of the upright parts of the base having a through hole; the through holes of the upright parts facing each other; the driven shaft being passed through the through holes of the upright parts of the base, and pivoted at two ends thereof on the lateral wall portions of the frame; and the stand being characterized by: the moving support member being coupled at lateral sides of two ends thereof to the loop-shaped motion units by means of a coupling structure; the moving support member having two front L-shaped sliding pieces, which have an L-shaped cross-section, and which are secured on front ends of both the lateral sides of the moving support member respectively; the moving support member having two rear L-shaped sliding pieces, which have an L-shaped cross-section, and which are secured on rear ends of both the lateral sides of the moving support member respectively; each of the L-shaped sliding pieces being inserted in a corresponding said hollow holding body of the frame from single one of two sides thereof, with said single side being propped against an inner side of a corresponding said first wall portion of the frame.
 2. The stand with lifting and lowering function as recited in claim 1, wherein one of the upright parts of the base of the frame have a hole, through which the output shaft of the driving unit is passed.
 3. The stand with lifting and lowering function as recited in claim 1, wherein the coupling structure includes: two laid-down U shaped pieces each secured on a respective said lateral side of the moving support member; each of the laid-down U shaped pieces having a containing hollowness, and a pair of opposing through holes on two opposing sides thereof; a section of each said loop-shaped motion unit being received in a corresponding said containing hollowness; said section of each said loop-shaped motion unit having a hole thereon; two threaded fixing elements, the threaded fixing elements being each passed through the opposing through holes of a respective said laid-down U shaped piece as well as said hole of a corresponding said loop-shaped motion unit; and two nuts, which are each securely joined to a respective said threaded fixing element.
 4. The stand with lifting and lowering function as recited in claim 1, wherein a space between two sides of each of the front L-shaped sliding pieces faces forwards, and a space between two sides of each of the rear L-shaped sliding pieces faces rearwards. 